BARILLA. ELMS. 73 
may be eaten as spinach, continue in season long after 
that plant is withered. The root is insipid and unpa- 
latable; but the stalks, and the stronger middle part of 
the leaves, may be stewed, or eaten plain-boiled, as 
asparagus. 
82. BARILLA is the Spanish name of a plant (Salsola 
soda)/nm the ashes of which is produced the salt called kali 
or soda. 
Soda is also procured from the ashes of PRICKLY SALTWORT 
(Salsola kali), SHRUBBY SALTWORT (Salsola fructicosa), and 
numerous plants of other tribes. 
On the shores of the Mediterranean, where the pre- 
paration of soda is pursued to considerable extent, the 
seeds of the plants from which it is obtained are regu- 
larly sown in places near the sea. When at a sufficient 
state of maturity, the plants are pulled up by the roots, 
dried, and afterwards tied in bundles to be burnt. Irr 
some places, this is done in ovens constructed for the 
purpose ; and in others, in trenches dug near the sea. 
The ashes, whilst they are hot, are continually stirred 
with long poles, and the saline matter they contain 
forms, when cold, a solid mass, almost as hard as stone. 
This mass is afterwards broken into pieces of convenient 
size for exportation. The best sort of Spanish soda is 
in dark-coloured masses of bluish tinge, very heavy, so- 
norous, dry to the touch, and it externally abounds in 
small cavities. Its taste is sharp, corrosive, and strongly 
saline. 
Soda is chiefly employed in glass and soap manufac- 
tories* See the uses of minerals, Vol. L No. 200. 
83. ELMS are forest-trees well known in almost every part 
of England. There are several species, of which, however, only 
three, the COMMON ELM (Ulrmis campestris, Fig. 61,) \v\cn 
HAZEL, or BROAD-LEAVED ELM (Uhnus montana, Fig. 62,) 
and DUTCH ELM (Ulmus suberosa), grow in this country with- 
out cultivation. They are easily distinguishable from most other 
forest-trees, by their leaves being rough, and doubly serrated at 
the edge. 
Of these trees theflozocrs of thejtrst are four-cleft, and have 
VOL. II. E 
